fs: protect inode->i_state with inode->i_lock
Protect inode state transitions and validity checks with the
inode->i_lock. This enables us to make inode state transitions
independently of the inode_lock and is the first step to peeling
away the inode_lock from the code.
This requires that __iget() is done atomically with i_state checks
during list traversals so that we don't race with another thread
marking the inode I_FREEING between the state check and grabbing the
reference.
Also remove the unlock_new_inode() memory barrier optimisation
required to avoid taking the inode_lock when clearing I_NEW.
Simplify the code by simply taking the inode->i_lock around the
state change and wakeup. Because the wakeup is no longer tricky,
remove the wake_up_inode() function and open code the wakeup where
necessary.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 4dda076..ed6fdcc 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1647,7 +1647,7 @@
};
/*
- * Inode state bits. Protected by inode_lock.
+ * Inode state bits. Protected by inode->i_lock
*
* Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
* I_DIRTY_DATASYNC and I_DIRTY_PAGES.
diff --git a/include/linux/quotaops.h b/include/linux/quotaops.h
index eb354f6..26f9e36 100644
--- a/include/linux/quotaops.h
+++ b/include/linux/quotaops.h
@@ -277,7 +277,7 @@
/*
* Mark inode fully dirty. Since we are allocating blocks, inode
* would become fully dirty soon anyway and it reportedly
- * reduces inode_lock contention.
+ * reduces lock contention.
*/
mark_inode_dirty(inode);
}